Green Chemistry. Barriers and pathways forward are considered. Green chemistry has a longer history, with principles established in the 1990s, said Julie Zimmerman, deputy director of the Center for Green Chemistry and Green Engineering at Yale University. In this lesson, the definition of green chemistry is presented. The grand technological challenges of sustainability and green chemistry's critical role for developing the technical dimension of a sustainable civilization are discussed. Green Chemistry. A traditional concept in process chemistry has been the optimization of the time-space yield. Green chemistry metrics are metrics that measure aspects of a chemical process relating to the principles of green chemistry. Green chemistry is the key to sustainable development, as it will direct the scientific community to the more persuasive and innovative solutions for the existing problems and will present opportunities for new processes and safer products in an economically competitive manner. The changes that are made to make chemistry “greener” can be economically beneficial for companies. Despite having smaller research and development divisions than large companies like SC Johnson Company, smaller companies are adopting green chemistry strategies as well. In the early 1990s, the term green chemistry was introduced by the Environmental Protection Agency, an agency of the US Government. Green Chemistry in Industry. Green chemistry is not the same as environmental chemistry. The 12 Principles of Green Chemistry according to the EPA: 1. Lesson One: The Essentials of Green Chemistry. These metrics serve to quantify the efficiency or environmental performance of chemical processes, and allow changes in performance to be measured. Prevent waste: Design chemical syntheses to prevent waste. From our modern perspective, this limited viewpoint must be enlarged, as for example toxic wastes can destroy natural resources and especially the means of livelihood for future generations. Leave no waste to treat or clean up. Green chemistry (sometimes referred to as sustainable chemistry) is the branch of chemistry that deals with the design and optimization of processes and products in order to lower, or remove altogether, the production and use of toxic substances. To better understand what is green chemistry, we will offer the definition coined by the EPA: “Green chemistry is the design of chemical products and processes that reduce or eliminate the use or generation of hazardous substances. Using the nonhazardous sorbent means that the hazardous sorbent is never manufactured and so the remediation technology meets the definition of green chemistry.” 1 . L'Oréal researchers chose to start with a natural sugar extracted from beech wood: xylose, a renewable raw material.It was ground, dissolved in water (a particularly harmless solvent), reacted in the presence of hydrogen and, after a few hours of agitation, heated slightly with a catalyst. 2. The EPA produced a set of 12 principles to guide the chemical industry (Table 1) and in this unit some of these principles will be explained, using wherever possible examples taken from subsequent units dealing with the manufacture of chemicals. Green Chemistry at work in cosmetics: the example of Pro-Xylane. Green chemistry seeks to streamline production processes, reduce the environmental impact of drugs and their metabolites, and minimize toxic chemicals used in reactions.